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arXiv · 2209.05331

Tailoring the Acidity of Liquid Media with Ionizing Radiation -- Rethinking the Acid-Base Correlation Beyond pH

Birk Fritsch·Andreas Körner·Thaïs Couasnon·Roberts Blukis·Mehran Taherkhani·Liane G. Benning·Michael P. M. Jank·Erdmann Spieker·Andreas Hutzler
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Abstract

Advanced in situ techniques based on electrons and X-rays are increasingly used to gain insights into fundamental materials dynamics in liquid media. Yet, ionizing radiation changes the solution chemistry. In this work, we show that ionizing radiation decouples the acidity from autoprotolysis. Consequently, pH is insufficient to capture the acidity of water-based systems under irradiation. Via radiolysis simulations, we provide a more conclusive description of the acid-base interplay. Finally, we demonstrate that acidity can be tailored by adjusting the dose rate and adding pH-irrelevant species. This opens up a huge parameter landscape for studies involving ionizing radiation.

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Birk Fritsch, Andreas Körner, Thaïs Couasnon, Roberts Blukis, Mehran Taherkhani, Liane G. Benning, Michael P. M. Jank, Erdmann Spieker, Andreas Hutzler. 2022-09-12. Tailoring the Acidity of Liquid Media with Ionizing Radiation -- Rethinking the Acid-Base Correlation Beyond pH. https://doi.org/10.1021/acs.jpclett.3c00593

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